Patent Literature 1 discloses a method for heating steel plate in a direct heat type of continuous heating furnace, which makes the temperature distribution in the width direction of the steel plate uniform. With this heating method, the steel plate is continuously passed through and heated in a direct heat type of continuous heating furnace. In this heating, prior to passing the plate through the direct-heat continuous heating furnace, the front and/or back side in the middle of the steel plate is coated with a substance having a emissivity that is higher than the emissivity of the steel plate. As a result, there is more radiant heat inputted to the middle part of the steel plate in the width direction, than at the edges. With this heating method, excessive heat is suppressed at the ends of the steel plate in the width direction, and this also promotes a rise in the temperature in the middle part, which makes the temperature distribution in the width direction of the steel plate more uniform.